Precise and flexible stimulus delivery and experimental control (SDEC) are essential for studies of perception and higher-cognitive functions. We have developed Presentation, a Windows SDEC program that delivers complex multimodal stimuli and monitors responses with precise timing. We now request Phase II support to add innovative new features to Presentation including (1) Adaptive stimulus delivery using the Presentation Control Language (PCL). PCL permits stimuli to be altered in real time based on performance or physiological responses, allowing automated adjustments in task difficulty, computer-controlled determination of neuronal receptive fields, and frame-by-frame display control important for computer-based neuro-rehabilitation. ((2) Graphic and audio stimulus generation using high-level Direct3D and DirectSound commands. These will permit auditory and visual stimuli to be defined and manipulated in 3D space. Stereovision and tactile stimulation capabilities will also be added sing DirectX 8.0 utilities. (3) A stimulus generation module interface (SGMI), permitting user programs to present custom stimuli during Presentation experiments. (4) Real-time streaming video with precise frame-by-frame control, making possible experiments with digitized and synthesized video sequences; (5) Easy-to-use tools for experiment creation and analysis to facilitate the development and analysis of experimental protocols. These additions will make Presentation an unexcelled SDEC platform for Phase III product launch. PROPOSED COMMERCIAL APPLICATION: Te proposed project will lead directly to a commercial PC-based stimulus delivery / experimental control software package.